Development and In-Vitro / In-Vivo Assessment of Extended Release Tablets of Nifedipine

Abstract

The aim of this study was to develop and evaluate single dose per day extended release tablet of nifedipine using Press coating techniques. Nifedipine solid state stability characterizations were investigated by HELOS, BET, and XRD. In the optimized batch, product NF5, in which combination approach using medium and lower grade viscosity of HPC was used to form the matrix tablet. The dissolution profiles of the nifedipine ER tablets were evaluated in comparison to the Procardia XL ® used as a reference dosage form. The innovator product design is based on complex osmotic pump technique, but the developed optimized formulation is based on a simpler technique using Press coating based design. The In-Vivo study was carried out using rabbit model. The In-Vivo results indicate that the HPC based tablet was capable of extending the drug release profile upto 24-hours. The In-Vivo pharmacokinetic results revealed no significant differences in Cmax, Tmax and AUC (0-24h) between test and reference products. The Tmax of the reference and test products were found to be 5.1 and 5.5 Hours, respectively. The maximum plasma drug concentration (Cmax) values of reference and test products were found to be 36.5±1.3 and 37.9±2.1 ng/L, respectively. The AUC (0 - t) and AUC (0 - ∞) value for reference and test formulations were found to be 612.40±22.7 μg/L*h, 656.35±15.7 μg/L*h and 600.20±31.54 μg/L*h, 641.54±24.5 μg/L*h respectively. The test product was found to be bio equivalent with reference product using simpler technique of press coating in comparison to complicated Osmotic based technique.